The broad, long term aims of this program are to describe the mechanisms of osmoregulation in the cell membranes of ocular epithelia and their possible derangement in ocular disease. In this period of support, membrane vesicles from the len's fibers and epithelium are used to detect mechanisms such as the Na+/H+ and Ca++/Na+ exchangers, the 2Cl-Na+K+ co-transporter and the Na+K+ ATPase. The activating effects of oxidative agents are tested on these membrane transport processes as well as the protection of natural antioxidating agents. Fluorescent probes SBFI for Na+, SNARF- l for H+, Fura 2 for Ca++ and SPQ for Cl- are used. The membrane mechanisms of ocular trabecular meshwork (TBM) cells in tissue culture will bc studied from the point of view of osmoregulation and contractile properties, utilizing imaging and quantitative microscopy. Adrenergic, cholinergic steroidal and oxidative agents will be tested on these TBM cell properties. Membrane events of human corneal epithelial cells (HCE) in tissue culture will be examined. Cell volume regulation and junction formation will be studied in the HCE transformed cell line utilizing imaging, quantitative microscopy and fluorescent probes. The work for this period will be of importance to the understanding of the formation of cataracts, the basic mechanisms of control of intraocular pressure and the cell biology of the corneal epithelium in health and disease.